Albert E. Mercker, 85, a potato production and marketing specialist with the Department of Agriculture for 36 years, died of a circulatory ailment Tuesday at his home in Washington.

He joined the Agriculture Department in 1918 as a market news investigator in Boston, later worked as a fruit and vegetable inspector in Chicago, and in 1922 became acting supervisor of inspectors in the New York area.

Mr. Mercker came to Washington in 1949 as a secretary of the Interstate Early Potato Committee, a project that helped adjust potato production in the southeastern states by promoting the growth and marketing of substitute crops.

During the mid 1930s, with the Agricultural Adjustment Agency, he helped develop the wider use of potatoes for livestock feed and as a source of starch.

He worked with the War Food Administration during World War II. During this time he helped develop plans for the production and distribution of both white and sweet potatoes to the armed forces. He also was instrumental in developing a potato dehydration program for the war years.

In 1947, Mr. Mercker toured nine European nations studying potato marketing and production problems. Later, as acting chief of Agriculture's potato division in 1948, he directed the shipping of more than 300,000 tons of American potatoes to war-ravaged Europe.

He retired from the Agriculture Department in 1956.

He then worked for a number of trade organizations, serving as director of the National Potato Council and executive secretary of the Vegetable Growers of America, before retiring a second time in 1974.

Mr. Mercker also taught for a time, starting an agricultural marketing program at North Carolina State University during the 1920s.

He was a native of Jersey City and earned a bachelor's degree in horticulture at Rutgers University. He worked his way through college as a produce handler in New York City.

Mr. Mercker served with the Army in Europe during World War I.

He had been a member of the Chevy Chase Citizens Association, the USDA Post of the American Legion, and the Masons.

He was a former president of both the D.C. Dahlia Society and the Gladiola Society of Washington.

Mr. Mercker was a congregational member of the Chevy Chase Baptist Church.

He is survived by his wife of 60 years, Frances, of the home; three sons, Albert E. Jr., of North Fork, Va.; Rodney C., of Callao, Va., and Donald F., of West Caldwell, N.J.; three sisters, Susan Porter, of Green Valley, Ariz.; Eleanor Feinen, of Aiken, S.C., and Eva, of Jersey City, and five grandchildren.